1. Field of the Invention
The present invention relates to a vehicle motor control apparatus for controlling the drive of a motor that is mounted on a vehicle and coupled with the engine, and more particularly to a vehicle motor control apparatus capable of raising the average torque so as to activate an engine rapidly and smoothly when the engine is restarted.
2. Description of the Related Art
Japanese Patent Laid-Open Pub. No. 2004-129379 discloses a conventional control apparatus for controlling the drive of a vehicle motor that is coupled with an engine. The control apparatus disclosed in Japanese Patent Laid-Open Pub. No. 2004-129379 utilizes a control method in which, when an engine is started, a method of energizing the respective phase of stator windings of the motor is switched from a 120-degree rectangular wave energization method to a 180-degree rectangular wave energization method.
In the motor control apparatus disclosed in Japanese Patent Laid-Open Pub. No. 2004-129379, the currents in the respective phase of stator windings of the motor flow in a current waveform decided by the 120-degree rectangular wave energization method or the 180-degree rectangular wave energization method; therefore, the output value of the motor can be nothing but the value decided by any one of the foregoing energization methods. Moreover, for the above reason, there has been a problem that the low-speed rotation (the 120-degree rectangular wave energization method) makes the current waveform rectangular and causes the torque ripple to increase.